Abrasive disk unit



Aug. 12, 1947. DQERMANN 2,425,368

ABRASIVE DISK UNIT Filed April 5, 1945 2 Sheets-Shed 2 Patented Aug.1947 A UNITED ABRASIVE DISK UNIT Albert J. Doermann, Chicago, Ill.,assignor to Titan Abrasives Company, a corporation of IllinoisApplication April 6, 1945, Serial No. 586,859

7 Claims. 1

This invention relates to abrasive disk units and more particularly toan arrangement whereby an abrasive disk assembly may be easily andquickly attached to and detached from its backing.

Abrasive disks are usually either fixedly mounted on backings at thefactory or must be attached to said backings at the place of use by alarge number of nuts and bolts or other fastening devices. In the firstplace, the backings must be returned to the factory to have new disksmounted thereon. In the second, a great deal of time and many operationsare necessary to remove and replace the disks. My invention permits themounting of the disk on the backing at the place of use with but twosimple operations, and but one looking action is necessary to hold itthere.

Another feature of my invention is the provision of means for tighteninga plurality of fastening devices with a single movement of the device towhich th'ey are attached. Another feature is means facilitating an easystart to such movement. Another feature is to provide a backing platefor an abrasive disk which may be reversibly mounted on a shaft andwhich therefore may be used with shafts rotating in opposite directions.

Other features and advantages of the invention will appear more fully asI proceed with the specification.

In the form of device embodying the features of my invention shown inthe accompanying drawings,

Fig. 1 is a side View, partly in section, of an abrasive disk mounted ona metal backing on the driving flange or wheel collar of a machineshaft;

Fig. 2 is a view taken as indicated by the line 22 of Fig. 1 with aportion in cross section;

Fig. 3 is a fragmentary View taken on the line- 33 of Fig. 1.

Fig. 4 is an enlarged cross sectional view taken on the line 4-4 of Fig.2; and

Fig. 5 is a view taken as indicated by the line 5-5 of Fig. 4.

As shown in the drawings, I indicates a disk of metal or other suitablematerial providing a backing plate for an abrasive disk assembly II(here shown as a single disk, although a segmental assembly isconventional in large grinders) which is molded of silicon of carbide,aluminum oxide or similar abrasive including emery, corundum, and thelike.

The backing I0 is provided with a plurality of slots I2 enlarged at oneend I3 for the reception of the heads I4 of studs I attached to nuts I6molded into the disk II. The balance of the slot is of a widthsufliciently larger than the body part of the studs I5 so that the studsmay fit snugly therein but without binding. Washers II, having flaring,corrugated or scalloped flanges I8, are also molded into the back of thewheel II, and with their openings aligned with the openings in the nutsI6. A suitable cement I9 may be used to more securely anchor the washerand nut in the abrasive disk II.

The stem of each stud I5 (shown as a stud bolt in the particularembodiment illustrated) is provided with a shoulder 20 above itsthreaded end portion and with another shoulder 2I spaced from the headI4. A split washer 22 is pinched around the stem above this shoulder 2|and pressed around the shoulder by means of spring '23. The edges of theslots I I are cut so that they taper outwardly and slope downwardly fromtheir mid portion to the enlarged portion I3 thereby forming inclinedportions 24 which terminate at the enlarged end portion I3 of the slots.

The backing plate is also provided with holes 25 countersunk on top andbottom for the reception of bolts 26 adapted to be extended intothreaded openings 21 in'the driving flange or wheel collar 28 of theshaft 29 on the machine with which the device is used to attach theassembly to said shaft. Hole v3!], extending from theoutereircumferential edge'3l of the backing plate III to one of theslots I2 therein, is provided for the reception of lock screw 32 havingtapered end '33.

The abrasive disk and its studs are adapted to be made and assembled atthe factory. Each stud I5 is provided with its head I4, spring 23, andsplit washer 22, and is then threaded into the nut I6 until the shoulder20 contacts the washer I? which limits its further movement. Whenreceived by theuser, the disk can be quickly 'mounted on the metalbacking plate byinserting the studs I 5 through the enlarged portions ofthe slots. When this is done, the shoulders 2| of the studs and thesplit washers 22 arelslightly above the ends of the inclined portions 24of the slots. The split washer with the spring pressing against itprovides limited play (as for example three hundredths of an inch in atwo foot diameter assembly I have built embodying these inventions) totake up variations in thickness of the mounting plate and the length ofthe studs.

The abrasive disk is then rotated to move the studs I5 in the slots IIuntil the studs contact the opposite ends 34 of the slots where they areheld in place by the action of the springs forcing &

wall 34 of the slots by the action just described,

the tapered end of the lock screw will force or jack them against suchwall when it is tight- 7 ened.

The inclined edges of the slots permit an easy starting movement of theabrasive disk, as the action of the springs does not take effect untilthe split washers 23 contact the inclined'p'ortion 24 which does notoccur until the disk has acquired some momentum.

It will be noted that the edges of' the slots are cut to form inclinedportions on both faces'of the backing plate and the center holes 26 ofthe backing are countersunk at both ends. This provides for reversiblemounting of the abrasive disks on the backing plate so that the platemay always be driven in the same direction relative to the slots, i. e.the enlarged end of the slot will always lead regardless of thedirection of movement of the driving shaft. This serves as an additionalanchoring means because movement of the abrasive disk due to frictionalresistance while grinding will force the studs [5 against the end wall34 of the slots and none of this force is exerted against the lockscrew.

From the above, it is apparent that the abrasive disk maybe easily andquickly placed on the backing plate and forced into the desired workingposition thereon whereby a plurality of studs are locked into positionwith one movenient and secured in such position with the locking action.The disk may be just as quickly replaced without removing the backingfrom'the machine. Thus, many men and machine hours are saved in mountingthe disks on the backing plate and but one backing plate is necessar foreach size of disk.

.While I have shown and described certain embodiments of my invention,it is to be understood that it Changes therefore in the construction andarrangement may be made without departing from the spirit and scope ofthe invention as disclosed in theappended claims in which it is myintention to claim all novelty inherent in my invention as broadly aspossible in view of the prior art.

What I claim and desire to secure by Letters Patent is: V

1. An abrasive disk unit comprising: backing plate means providedv witha plurality of slots;

an'abrasive disk assembly having studs with enlarged heads extendingfrom the rear'face thereof, said slots having enlarged ends forreceiving is capable. of many modifications,

4, Y of a size to snugly receive said stud; and resilient means on saidstuds to clamp them to the backing plate. V j r 2. A device a claimed inclaim -1 in Which the slots extend from one face to the other of thebacking member and'the edges of the slots are tapered toward theenlarged portions on both faces of the backing member.

3. A device as claimed in claim l'in which the clamping means is awasher and spring around the studs and adjacent the'heads thereof.

4. An abrasive disk unit comprising; a backing plate means providedwith'a plurality of slots each'havin'g an enlarged end portion, the edgeof said slots tapering toward said enlarged end; an

abrasive disk assembly having studs with enlarged heads each having ashoulder spaced from said head and lying above the end of said taperededges of the slots when the studs are inserted into the slots; a washeron each of said shoulders; and a spring around each stud between thehead and washer to force the washer against the shoulder.

5. An abrasive disk unit'comprising': a backing plate provided with aplurality of slots; an abrasive disk having studs with enlarged headsextending from the rear face thereof, said slots having enlarged endsfor receiving said studs, the opposite ends of said slots being of asize to snugly receive said studs; means on said studs to clamp them tothe backing plate; and means for one'of said studs and force itagainstthe smaller end of its slot.

7. An abrasive disk unit comprising: i an abrasive disk assembly havingstuds with en-' larged heads extending from one face thereof;

and backing plate means provided with a plu rality of concentricallyarranged arcuate slots, said slots having enlarged portions at one endfor receiving the heads of said studs, the oppo site ends of said slotsbeingof a size to snugly receive said studs, the enlarged ends of saidslots being on the leading end of the slot with respect Number Name fDate 2,351,129 JOCkBl i June 13, 194:4:

1,733,723 Doermann Oct. 29, 1929 1 ,812,076 Beebe June 30, 19312,279,278 Shue Apr. 7, 1942' 1,964,537 7 Shue June 26, 1934 2,378,271Whl1dOn June 12, 1945 1,670,302 'Finnell May 22, 1923 said studs, theopposite'ends of said slots being v to the direction of rotation of theunit. ALBERT J. DOERMANN.

' REFERENCES CITED 7 The following references are' of record in the fileof this patent: V

UNITED STATES PATENTS 1,835,573 Ponselle Dec. 1931

